This invention relates to non-contact optical dimension gauging instruments, commonly referred to as optical or laser micrometers.
Optical micrometers are especially useful when it is desired to measure the dimension of articles without physically contacting the articles. Examples of optical or laser micrometers are shown in the following U.S. Pat. Nos.
3,812,685, PA1 3,565,774, PA1 3,592,545, PA1 3,743,428, PA1 3,853,406, PA1 3,961,838, PA1 3,856,411, PA1 3,856,412, PA1 3,868,437, PA1 3,870,890, PA1 3,905,705.
The accuracy to which prior art optical micrometers measure the dimension of the article placed within the zone of measurement has depended in part upon the linearity of the optical system, the stability of the scanning mechanism and high frequency clocks, or in maintaining the relationship between calibrating devices and the measurement path.